Referring now to FIG. 1A, an airbag restraint system (ARS) 10 that deploys one or more airbags in the event of a collision is shown. The ARS 10 comprises an airbag control system (ACS) 11 that detects the collision, an inflator 14, and an airbag 16. The ACS 11 includes a crash sensor 12 and a control module 13. The crash sensor 12 senses the force of impact when a collision occurs. When the force is greater than a predetermined value, the crash sensor 12 generates a control signal. On receiving the control signal, the inflator 14 inflates the airbag 16. The control module 13 comprises control circuitry that controls the operation of the ARS 10.
Referring now to FIG. 1B, an ARS 20 that deploys one or more airbags in the event of a rollover is shown. The ARS 20 comprises an ACS 21 that detects the rollover, an inflator 24, and an airbag 26. The ACS 21 includes a rollover sensor 22 and a control module 23. The rollover sensor 22 senses a roll angle of the vehicle when rollover is imminent. When the roll angle is greater than a predetermined value, the rollover sensor 22 generates a control signal. On receiving the control signal, the inflator 24 inflates the airbag 26. The control module 23 comprises control circuitry that controls the operation of the ARS 20.
Mechanical switches are typically used to disable deployment of airbags during maintenance operations. Mechanical switches may, however, become inoperative over time. Consequently, airbags may inadvertently deploy during maintenance operations. Particularly, ACSs that detect rollovers may deploy airbags when the ACSs are being removed from vehicles for maintenance purposes while power to the ACSs is on.